POTASSIUM CHANNELS ON CARDIOMYOCYTES OF SELENIUM IODINE DEFICIENCY RATS AND IODINE DEFICIENCY RATS

INTRoDUt?Tl()NOneofthemainpathogenicfact()rofKeshandis-easeisselensiumdeflclencythatisprevaillngonalongstripregionfromeasttosouthwestinourcountry'Theiodinedeficiencydiseaselsendemicall()verourcountryexceptShanghai.Accordingtt)theinf()rmationofgeochem1stry,thesoilofepidemlcregioncontalnsmuchlessseleniumandiodinethanthatofnodiseaseregiondoes-Therefore,theseleniumandiodineinfoodproducedfromKeshandiseaseregionislessthannormalvalue.SeleniumisanessaserycomponentofSe(iSHPx(seleniumdependentglut…

POTASSIUM CHANNELS ON CARDIOMYOCYTES OF SELENIUM IODINE DEFICIENCY RATS AND IODINE DEFICIENCY RATS

Using diet control method to feed the weaning male Wistar rats with selenium and iodine deficiency Keshan endemic area food for 8 weeks to set up animal model. Singal channel recording in cell attached model was used to measure cardiac cell membrane potassium channel conductances, which coincide with the cardiac cell membrane potassium channel conductances in normal Wistar rats. The potassium channel conductance on selenium and iodine deficiency rat cardiac cell membrane is showing current-voltage increasing lineally in the range of clamping voltage 0 +/- 30 mV with channel conductance of 43.4 pS. The channel current does not increase depending on the clamping voltage that is showing the rectifying characteristic and the channel current amplitude can be augmented by added KIOa 5 mmol/L in bath solution. A kind of inward rectifying potassium channel activity was recorded, but this channel activity disappeared after lasting 6-10 minutes only. Then an inward rectifying potassium channel with the conductance of 14.2 pS was activated by KIOa 5 mmol/L introduced to bath solution. Both conductances are less than that of normal Wistar rats.